Pre-crimp balloon inflation

A method of crimping a stent onto a balloon of a stent delivery catheter, the method comprising:

• providing a crimping apparatus including a plurality of crimping elements forming a crimping lumen having a diameter, wherein the plurality of crimping elements are actuatable to alter the diameter of the crimping lumen;
• positioning a stent loaded onto an inflation balloon of a stent delivery catheter within the crimping lumen of the crimping apparatus;
• inflating the inflation balloon within the stent to a pressure of 4 atmospheres or less;
• actuating the crimping elements radially inward toward the stent to apply a radially compressive crimping force to the stent while the inflation balloon is inflated, wherein balloon material is projected radially outward through interstices of a first end segment of the stent proximate a first end of the stent, and wherein balloon material is projected radially outward through interstices of a second end segment of the stent proximate a second end of the stent;
• maintaining the radially compressive crimping force for a duration of time;
• deflating the inflation balloon while maintaining the radially compressive crimping force, wherein balloon material remains projected radially outward through the interstices of the first end segment of the stent proximate the first end of the stent after deflating the balloon;
• and wherein balloon material remains projected radially outward through the interstices of the second end segment of the stent proximate the second end of the stent after deflating the balloon;
• and
• actuating the crimping elements radially outward away from the stent to discontinue the radially compressive crimping force, wherein balloon material remains projected radially outward through the interstices of the first end segment of the stent proximate the first end of the stent after discontinuing the radially compressive crimping force;
• and wherein balloon material remains projected radially outward through the interstices of the second end segment of the stent proximate the second end of the stent after discontinuing the radially compressive crimping force.

A method of securing a stent onto a balloon of a stent delivery catheter, the method comprising:

• providing a stent loaded onto an inflation balloon of a stent delivery catheter, the stent having a first end, a second end and a length measured from the first end to the second end, and an outer peripheral surface, an inner peripheral surface and a thickness measured from the outer peripheral surface to the inner peripheral surface, the stent including:
• a first longitudinal length of interconnected struts extending from the first end of the stent toward the second end of the stent, the first longitudinal length of interconnected struts defining interstices between adjacent interconnected struts of the first longitudinal length of interconnected struts,
• a second longitudinal length of interconnected struts extending from the second end of the stent toward the first end of the stent, the second longitudinal length of interconnected struts defining interstices between adjacent interconnected struts of the second longitudinal length of interconnected struts,
• a third longitudinal length of interconnected struts extending intermediate the first longitudinal length of interconnected struts and the second longitudinal length of interconnected struts, the third longitudinal length of interconnected struts defining interstices between adjacent interconnected struts of the third longitudinal length of interconnected struts;
• providing a crimping apparatus for crimping the stent onto the inflation balloon of the stent delivery catheter;
• positioning the stent loaded onto the inflation balloon of the stent delivery catheter within the crimping apparatus;
• pressurizing the inflation balloon within the stent;
• crimping the stent onto the inflation balloon while the inflation balloon is pressurized;
• inducing balloon material of the balloon radially outward through the interstices of the first longitudinal length of interconnected struts from the inner peripheral surface toward the outer peripheral surface of the stent greater than half the thickness of the stent during the crimping step;
• inducing balloon material of the balloon radially outward through the interstices of the second longitudinal length of interconnected struts from the inner peripheral surface toward the outer peripheral surface of the stent greater than half the thickness of the stent during the crimping step;
• not inducing balloon material of the balloon radially outward through the interstices of the third longitudinal length of interconnected struts from the inner peripheral surface toward the outer peripheral surface of the stent greater than half the thickness of the stent during the crimping step;
• and
• removing the stent and inflation balloon from the crimping apparatus.

A method of crimping a stent onto a balloon of a stent delivery catheter, the method comprising:

• providing a crimping apparatus;
• loading a stent onto a balloon of a stent delivery catheter;
• positioning the stent and the balloon of the stent delivery catheter within the crimping apparatus;
• crimping the stent onto the balloon with the crimping apparatus;
• pressurizing the balloon to an inflation pressure less than 6 atmospheres but greater than 0.4 atmospheres during the step of crimping the stent onto the balloon;
• depressurizing the balloon after the step of pressuring the balloon, but while the stent and the balloon remain positioned within the crimping apparatus;
• and
• removing the stent and the balloon from the crimping apparatus after the step of depressurizing the balloon.

A stent delivery system, comprising:

• a stent delivery catheter including an elongate shaft and an inflation balloon secured to the elongate shaft;
• a stent loaded onto the inflation balloon, the stent having a first end, a second end and a length measured from the first end to the second end, and an outer peripheral surface, an inner peripheral surface and a thickness measured from the outer peripheral surface to the inner peripheral surface, the stent including:
• a first portion of the stent extending from the first end of the stent toward the second end of the stent, the first portion of the stent including a plurality of interconnected struts defining interstices between adjacent interconnected struts of the first portion of the stent,
• a second portion of the stent extending from the second end of the stent toward the first end of the stent, the second portion of the stent including a plurality of interconnected struts defining interstices between adjacent interconnected struts of the second portion of the stent,
• a third portion of the stent located intermediate the first and second portions of the stent, the third portion of the stent including a plurality of interconnected struts defining interstices between adjacent interconnected struts of the third portion of the stent;
• wherein balloon material of the balloon extends radially outward through the interstices of the first portion of the stent from the inner peripheral surface toward the outer peripheral surface of the stent greater than half the thickness of the stent;
• wherein balloon material of the balloon extends radially outward through the interstices of the second portion of the stent from the inner peripheral surface toward the outer peripheral surface of the stent greater than half the thickness of the stent;
• and
• wherein balloon material of the balloon does not extend radially outward through the interstices of the third portion of the stent from the inner peripheral surface toward the outer peripheral surface of the stent greater than half the thickness of the stent.